The two major functions of the Cell Culture Module are (1) to help investigators use cultures effectively in their research, and (2) to provide a mechanism for optimum sharing of ocular specimens from human and animal eyes. To fulfill the first function, the Module: (a) serves as a repository for several types of cultured ocular cells and cell lines, (b) provides a centralized facility with shared-use equipment for culture maintenance for those who lack culture facilities in their own labs, (c) provides some shareduse instruments (such as inverted phase and fluorescence photomicroscopes) for investigators who have basic culture facilities to avoid duplication of all equipment, and (d) assists investigators in using in vitro models for their work including bringing culture methods into their own labs by training laboratory personnel in culture techniques. The availability of this Module also improves the economy of our lab operations since common-use culture supplies can be purchased in bulk.